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<td><b><dl><dt>Berkeley DB Reference Guide:<dd>Upgrading Berkeley DB Applications</dl></b></td>
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<p align=center><b>Release 3.0: the DB structure</b></p>
<p>The <a href="../../api_c/db_class.html">DB</a> structure is now opaque for applications in the Berkeley DB 3.0
release.  Accesses to any fields within that structure by the application
should be replaced with method calls.  The following example illustrates
this using the historic type structure field.  In the Berkeley DB 2.X releases,
applications could find the type of an underlying database using code
similar to the following:</p>
<blockquote><pre>DB *db;
DB_TYPE type;
<p>
	type = db-&gt;type;</pre></blockquote>
<p>in the Berkeley DB 3.X releases, this should be done using the
<a href="../../api_c/db_get_type.html">DB-&gt;get_type</a> method, as follows:</p>
<blockquote><pre>DB *db;
DB_TYPE type;
<p>
	type = db-&gt;get_type(db);</pre></blockquote>
<p>The following table lists the <a href="../../api_c/db_class.html">DB</a> fields previously used by
applications and the methods that should now be used to get or set them.</p>
<table border=1 align=center>
<tr><th><a href="../../api_c/db_class.html">DB</a> field</th><th>Berkeley DB 3.X method</th></tr>
<tr><td>byteswapped</td><td><a href="../../api_c/db_get_byteswapped.html">DB-&gt;get_byteswapped</a></td></tr>
<tr><td>db_errcall</td><td><a href="../../api_c/db_set_errcall.html">DB-&gt;set_errcall</a></td></tr>
<tr><td>db_errfile</td><td><a href="../../api_c/db_set_errfile.html">DB-&gt;set_errfile</a></td></tr>
<tr><td>db_errpfx</td><td><a href="../../api_c/db_set_errpfx.html">DB-&gt;set_errpfx</a></td></tr>
<tr><td>db_paniccall</td><td>DB-&gt;set_paniccall</td></tr>
<tr><td>type</td><td><a href="../../api_c/db_get_type.html">DB-&gt;get_type</a></td></tr>
</table>
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